docs: def reset(self, label=None):
          """
          clears all measurements, allowing the object to be reused
  
          Args:
              label (str, optional) : optionally change the label
  
          Example:
              >>> from timerit import Timerit
              >>> import math
              >>> ti = Timerit(num=10, unit='us', verbose=True)
              >>> _ = ti.reset(label='10!').call(math.factorial, 10)
              Timed best=...s, mean=...s for 10!
              >>> _ = ti.reset(label='20!').call(math.factorial, 20)
              Timed best=...s, mean=...s for 20!
              >>> _ = ti.reset().call(math.factorial, 20)
              Timed best=...s, mean=...s for 20!
          """
          if label:
              self.label = label
          self.times = []
          self.n_loops = None
          self.total_time = None
          return self